In the field of marine operations, operations at sea are often carried out with vessels. An operation may be a lifting operation, a pipeline laying operation, an installation operation or a removal operation of a structure such as a wind turbine or a drilling platform, a rescue or salvage operation, a drilling operation for drilling hydrocarbons. Other operations may be a loading or unloading operation of a vessel at sea. Other operations may include the collecting and processing of hydrocarbons on an FPSO or other kind of vessel, or the unloading of the collected hydrocarbons from the FPSO to a shuttle tanker.
Other operations may include the launch of a space rocket from a marine platform or the collecting of data with a research vessel. Many other operations are performed at sea in the field of the art.
Generally, wind, waves and currents exert forces on the vessel, which forces cause movements of the vessel. In some cases, the natural period of the waves approximates or equals the natural period of a vessel. In that case, the vessel may tend to roll to substantial roll angles and have motions which are undesirable.
In some cases, these motions hinder the execution of the operation itself. It may be desirable to reduce the motions of the vessel at certain times.